Fish emulsion

Fish emulsion is made by processing fish or fish waste into a stabilised liquid, often through partial enzymatic or heat breakdown. The result is a nutrient solution dominated by nitrogen, with lower phosphorus and potassium and a spread of micronutrients derived from the fish tissue. Exact analysis varies by product.

Source

Processed fish and fish-processing by-products

Primary nutrient

Nitrogen, with smaller amounts of phosphorus and potassium

Micronutrients

A range of trace elements from the fish tissue

Physical form

Liquid concentrate, diluted with water before application

Fish emulsion supplies nitrogen as its main nutrient, in a partly soluble organic form that becomes available relatively quickly, along with modest phosphorus and potassium and a range of micronutrients. Its readily available nitrogen gives a prompt response but a shorter-lived effect than slow-release solids.

• Nitrogen is the dominant nutrient and is available relatively quickly
• Phosphorus, potassium, and micronutrients are supplied in smaller amounts
• Effect is prompt but shorter-lived than from slow-release organic solids

Fish emulsion is used in organic and horticultural systems as a quick feed, applied diluted as a foliar spray or through fertigation to seedlings, transplants, and container crops. Its fast, gentle action suits frequent light feeding rather than a single large application.

• Accepted as an input in many organic farming standards
• Well suited to foliar feeding, fertigation, and container or transplant crops
• Best used as regular light feeds rather than one large dose

Fish emulsion is a relatively low-analysis, more costly nutrient source per unit of nitrogen, so it is impractical for supplying large amounts of nitrogen to field crops. It has a strong odour, and concentrated or repeated foliar sprays can scorch sensitive foliage if not properly diluted.